Magnetic levitation devices generally use magnetic means such as permanent magnets or electromagnets to create a vertical magnetic field at the levitation position. The most common magnetic levitators since the 1950's have used a controllable electromagnet, or other strong magnet, positioned above a levitating object made from Ferromagnetic material. For example, U.S. Pat. No. 2,691,306, issued to Beams, discloses a device wherein the levitating object may be spun at high speed below an electromagnet. The device counters gravity by producing a ferromagnetic force. The force is variable in the vertical direction to stabilize the levitating object at the desired level.
Other similar devices involve novelties such as magnetically levitating world globes. U.S. Pat. No. 4,382,245, issued to Harrigan, discloses a naturally stable magnetic levitator wherein a floating, spinning magnet levitates above another, permanent magnet. U.S. Pat. No. 4,585,282, issued to Bosley, discloses a feedback levitator with magnets and controllable electromagnets below the levitating magnet. U.S. Pat. No. 5,168,183, issued to Whitehead, improved on Bosley by reducing the unstable plane to a single direction, which simplified the sensing and control. The Whitehead and Bosley devices allow a levitating magnet to float over a base magnet with the aid of controllable electromagnets.
United States Published Patent Application Number 2008/0122308, filed by Mleux, discloses position dependent control systems for a rotor or train car suspended in a vertical magnetic field created by magnetic structures above and below the levitated object. Lorentz forces between currents in fixed wires and magnets on the floater limit excursions of the floater between two positions around the equilibrium point. This requires narrow gaps between the structure and the levitated rotor.
These references share many common features, mainly which require the primary magnetic field created by the fixed magnets or electromagnet to be in the vertical or z-direction at the levitation point. Moreover, the poles of the floating, or induced magnet, are also in the vertical or z-direction. Finally, a gradient of the vertical or z-component of the magnetic field provides the lifting force against gravity. This usually requires the magnetic means to be located above and/or below the levitating object.
Academics have studied naturally stable levitation using diamagnetic materials. The journal article entitled, “Diamagnetically Stabilized Magnet Levitation,” by Martin Simon, the named and sole inventor of the present invention, discloses a horizontally stable levitation device that uses diamagnetic materials and requires no additional energy input. Although effective, diamagnetic materials provide a very weak repelling force that decreases rapidly with distance and therefore must be located within a few millimeters of the levitating magnet. This method is not suitable for applications where there needs to be significant clear space around the levitated magnet platform or the magnet platform is operating in a closed or restricted cavity.
Thus, what is needed is a device that creates a magnetic field with the primary magnetic field in the horizontal direction at the levitation position, which will allow a magnetic means to be located in between the fixed magnets without a magnetic means above or below the levitating object, and without using diamagnetic materials to stabilize the levitating object.